Entergy Arkansas, Inc' Proposed Transmission Projects

1
Entergy Arkansas, Inc.Proposed
TransmissionProjects

• Entergy Transmission Planning Summit
• New Orleans, LA
• July 31, 2007

2
2007 - 2008 EAI Transmission Projects
1
1.) Hilltop New Ring Bus at Intersection of EAI
and SPA lines
2.) Dewitt Capacitor Bank
2
Carryover from 2006
2007/2008 Projects
3
2009-2010 EAI Transmission Projects
1.) Grandview 161kV Substation
2.) Dell 161kV Reactor Replacement
1
2
3.) Cabot 500/115kV Substation
3
4
2011-2012 EAI Transmission Projects
2.) Re-conductor 115kV Transmission Line from
Corning to Texas Eastern 8
2
1.) Gobel - 230/115 kV Substation
1
5
Hilltop 161 kV Ring BusBetween EAI and SPA Lines
2007

• Scenario
• The 161 kV transmission system in northwest
  Arkansas is generally served by generation
  located at Arkansas Nuclear One (ANO) and
  Independence SES (ISES).
• There are also units at Table Rock, Ozark Beach,
  Norfork and Bull Shoals Dam which provide some
  support during the summer peak, but availability
  of these resources is limited by the availability
  of water on their respective sources.
• Three major transmission lines which originate at
  Harrison East and cause undervoltages and thermal
  overloads
• Harrison East Eureka Springs 161 kV
• Harrison East Bull Shoals Dam 161 kV
• Harrison East Quitman 161 kV
• Proposed Solution
• Build a four-breaker ring bus, Hilltop, where the
  SPA line from Dardanelle - Bull Shoals crosses
  the APL line from Harrison East - Quitman.
• Estimated Cost 8.6 M

6
Hilltop 161 kV Ring Bus
Hilltop Install New Ring Bus
7
Thayer South Install New 161 kV Intertie w/ AECI

• Project Cancelled
• AECI elected to connect to an existing AECI owned
  161kV Station

8
Thayer South Install New 161 kV Intertie w/ AECI
(Cancelled)
9
Dewitt 32.4 MVAR Capacitor Bank
2008

• Scenario
• Loss of the Helena Industrial - Ritchie SES 115
  kV line segment causes low voltages at various
  substations
• Loss of the Stuttgart Ricusky 230/115 kV
  autotransformer causes low voltages at various
  substations and overloads on the Woodward
  Altheimer and the Altheimer Wabbaseka 115 kV
  line segments
• Proposed Solution
• Install a 32.4 MVAR capacitor bank at Dewitt.
• Correct Distribution power factor at Dewitt,
  Almyra, Marvell, Gillett, Helena Central, and Ulm
  substations.
• Estimated Cost 880 K

10
Dewitt 32.4 MVAR Capacitor Bank
Dewitt 32.4 MVAR Capacitor Bank
11
Maumelle East Substation Install 2nd T-Line
2008

• Scenario
• Significant load growth in the Maumelle area
  justified removing Maumelle East from radial
  service.
• The loss of the Maumelle East Maumelle SS line
  results in a complete outage to the Maumelle
  area.
• Proposed Solution
• Construct a parallel 115kV line from Maumelle SS
  to Maumelle East to establish dual line service.
• Estimated Cost 3 M

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Maumelle East 2nd Transmission Line
Maumelle East 2nd Line
13
Dell 161kV Reactor Replacement
2010

• Scenario
• The 161kV reactor at Dell failed late 2006.
• During off-peak, low load periods, the voltage at
  Dell EHV reaches 1.05pu on the 500kV and 161kV
  systems.
• Proposed Solution
• The failed 161kV 50MVAR reactor at Dell will be
  replaced with 2-161kV, 30 MVAR reactors
• Estimated Cost 1.5 M

14
Dell 161kV Reactor
Replace Dell 161kV Reactor
15
Osage Creek-Grandview
2010

• Scenario
• By 2010 it is estimated that approximately 227 MW
  of load will be served between Harrison East and
  Eureka Springs.
• Nearly 110 MW of the load will be located at
  Osage Creek, at the extreme northwest end of the
  line.
• Loss of the Harrison East Harrison South
  transmission line segment causes thermal
  overloads by as much as 7 on the Eureka Osage
  Creek (AECC) line segment and leaves over 30 MW
  at risk.
• Loss of this line also causes Osages voltage
  drop to 73.
• Proposed Solution
• Construct a new switching station, Grandview, on
  the transmission line from Table Rock Dam
  Eureka Springs. Build a new line between
  Grandview and Osage Creek.
• Estimated Cost 5.8 M

16
Osage Creek-Grandview
Grandview
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Cabot 500/115kV Substation
2010

• Scenario
• For the past two summers, several stations in
  Little Rock observed voltages as low as 91 of
  nominal with no significant contingencies.
• The loss of one of the 500/115kV transformers at
  Mabelvale in 2006 resulted in widespread low
  voltages in the Little Rock area.
• With the loss of one 500/115kV transformer at
  Mabelvale, a loss of the second transformer (N-2)
  would cause the voltage to collapse and
  widespread outages in the Little Rock area.
• Proposed Solution
• Construct a 500/115kV substation near Cabot
  Northeast of Little Rock. This will provide
  voltage support to Little Rock and reduce some
  thermal contingencies.
• Estimated Cost 19 M

18
Cabot 500/115kV Substation
Cabot EHV
19
Gobel 230/115 kV Substation
2011

• Scenario
• Loss of the Helena Industrial - Ritchie SES 115
  kV line segment causes
• Low voltages at Helena Central, Barton, Marvell,
  Elaine, Gillette, Deluce, and Dewitt
• Loss of the Stuttgart Rickusky 230/115 kV
  autotransformer causes
• Low voltages at Almyra, Deluce, Gilette, Dewitt,
  Stuttgart North, Stuttgart Ricusky, Ulm,
  Wabbaseka, and Stuttgart Industrial
• Overloads the Woodward Altheimer 115 kV line
  segment
• Overloads the Altheimer Wabbaseka 115 kV line
  segment
• Proposed Solution
• Build a 230/115kV Substation at the crossing of
  the 115kV transmission line from Marvell to
  Elaine and the 230kV transmission line from
  Ritchie to Stuttgart Ricusky.
• Estimated Cost 9 M

20
Gobel 230/115 kV Substation
Gobel 230/115kV Substation
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Re-conductor Corning - Texas Eastern 8 115 kV
line
2011

• Scenario
• Previous construction has increased the conductor
  size on selected spans to 1590 MCM and 666 MCM,
  but a majority of the line is 336 MCM or smaller
  (e.g., 4/0 copper), and substation equipment
  limits the ampacity of the line.
• The voltage drop from TE 8 to Corning exceeds
  22 under certain single contingency scenarios.
• Low voltage also causes greater current to flow
  and will cause a 190 overload on the Corning to
  TE 8 line segment.
• Proposed Solution
• Rebuild the line segment from Corning to TE 8
  with 666 MCM, to increase the line rating to 176
  MVA.
• Estimated Cost 3 M

22
Re-conductor Corning - Texas Eastern 8 115 kV
line
Upgrade 115kV Line
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Transmission System Target Areas 2013 and Beyond

• 1.) Jonesboro Area
• Line Upgrade

1

• 2.) Little Rock Area
• Additional Reactive Support

2

• 3.) Hot Springs Area
• Line Upgrade
• New 115kV Switching Station

3

• 4.) El Dorado Area
• 2 New 115kV Transmission Lines
• Line Upgrades

4